Nebulizer

ABSTRACT

A nebulizer comprises a controller linked at its output to a nebulizer head, and at its input to a USB cable and USB plug for connection to a host system. The link between the USB plug and the controller is a USB cable with power and data channels. The controller comprises a boost circuit, a microcontroller 11, and a drive circuit. The latter provides power and control signals via a cable and proprietary plug to the nebulizer head. These signals provide power and control for a vibrating membrane receiving a liquid to be aerosolised. The controller has a housing with LED status lamps, and an ON/OFF button. The controller can be controlled via a host, either locally or remotely.

INTRODUCTION CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of U.S. provisionalapplication Ser. No. 61/642,284, filed on May 3, 2012, the contents ofwhich are herein incorporated by reference in their entirety.

FIELD OF THE INVENTION

The invention relates to a nebulizer, and more particularly to powersupply and control of aerosol generation in nebulizers.

PRIOR ART DISCUSSION

Aerosol delivery systems can aerosolise a broad range of liquids acrossa particle range 1-50 μm MMAD. Such systems have an aperture plate withholes of pre-determined size and which is coupled with a vibrationalmechanism powered by a piezo. The aperture plate is vibrated at afrequency of typically 120 to 150 kHz and this action causes the liquidto break surface tension and it creates an aerosol plume as dropletspass through the aperture plate. An example is described in WO2010035252(Stamford Devices Ltd).

WO2012/026963 (Rubin) describes an aerosol delivery system having anintegral USB plug.

SUMMARY OF THE INVENTION

According to the invention, there is provided a nebulizer comprising anebulizer head for generating an aerosol, a controller for deliveringpower and control signals to the nebulizer head, and a standarduniversal bus for delivering power and control signals to thecontroller,

-   -   wherein the standard universal bus comprises a universal plug        and a universal cable extending from said plug to the        controller,    -   wherein the controller is linked by a cable and a plug to the        nebulizer head; and    -   wherein the controller comprises a voltage boost circuit linked        at its input with the universal bus, a processor, and a drive        circuit for delivering power to the nebulizer head under control        of the processor.

In one embodiment, the universal bus is a USB bus, and wherein totalpower requirement of the controller and of the nebulizer head fallswithin the power specification of the standard USB protocol.

In one embodiment, the controller provides to the nebulizer head no morethan 500 mA at nominal 5V.

In one embodiment, the drive circuit is adapted to generate a waveformin the range of 120 kHz and 150 kHz.

In one embodiment, the boost circuit is adapted to generate a voltagesupply for the processor and the drive circuit. Preferably, the voltagelevel is 12 V.

In one embodiment, the processor is adapted to upload the followinginformation to a host via the universal bus:

-   -   power consumption, and/or    -   wet/dry state of the nebulizer head, and/or    -   nebulizer disconnect status, and/or    -   cable disconnect status, and/or    -   error or fault states, and/or    -   nebulization duration and time of nebulization.

In another embodiment, the controller is adapted to receive thefollowing signals from a host via the universal bus and to use them togenerate nebulizer head drive signals:

-   -   nebulization start/stop, and/or    -   nebulization time, and/or    -   nebulization flow rate, and/or    -   nebulization pulse rate, and/or    -   inspiratory/expiratory signal to enable phased nebulization

In another aspect, the invention provides a nebulizer system comprisinga nebulizer as defined above in any embodiment, and a host systemadapted to provide control signals to the controller via said bus.

In one embodiment, the host system is adapted to provide the controlsignals according to a patient dosing regime.

In one embodiment, the host system includes a component adapted tocommunicate with a remote server for download of control instructionsand/or upload of nebulizer data.

In one embodiment, the host system includes a portable device such as asmartphone or tablet computer.

DETAILED DESCRIPTION OF THE INVENTION

The invention will be more clearly understood from the followingdescription of some embodiments thereof, given by way of example onlywith reference to the accompanying drawings in which:

FIG. 1 is a block diagram illustrating architecture of a nebulizer ofthe invention; and

FIG. 2 is a perspective view of the nebulizer.

FIG. 3 shows the nebuliser in use in one example with the controllerattached to a ventilation tube.

DESCRIPTION OF THE EMBODIMENTS

Referring to the drawings, a nebulizer 1 comprises a controller 2 linkedto a vibrating mesh nebulizer head 3. The nebulizer 1 also comprises aUSB plug 4 for connection to a host system or device.

The link between the USB plug 4 and the controller 2 is a USB (UniversalSerial Bus) cable 5 with power and data channels. The link between thecontroller 2 and the nebulizer head 3 is a proprietary cable 6 withpower and data channels and a proprietary plug 7.

The controller 2 comprises a boost circuit 10 consisting of a customoptimized high frequency, high efficiency DC to DC converter with anintegrated power switch capable of providing an output voltage andcurrent profile suitable to drive the nebulizer load, There is also adrive circuit 12 utilizing a series inductor to generate the alternatingAC voltage. The drive circuit 12 incorporates a high speed MOSFET drivercontrolled by a pulse width modulated signal from the microcontroller.There is also a microcontroller 11 with an integrated peripheral modulefeaturing a full speed USB 2.0 compliant interface that canautomatically change clock sources and power levels upon connection to ahost. The latter provides power and control signals via the proprietarycable 6 and the proprietary plug 7 to the nebulizer head 3. Thesesignals provide power and control for a vibrating membrane receiving aliquid to be aerosolised from a feed container. An example of thenebulizer head is described in our previous PCT applicationWO2012/046220. The controller 2 and the nebulizer head 3 require no morethan 500 mA at nominal 5V to generate a desired aerosol.

The controller 2 has a housing 25 with LED status lamps 30, and anON/OFF button 32. Communication takes place between the controller 2 andthe USB plug 4 in compliance with the USB protocol.

The nebulizer drive circuit 12 consists of components to generate anoutput sine waveform of approximately 100V AC which is fed to thenebulizer head 3, causing aerosol to be generated. It uses inputs fromthe microcontroller 11 and the boost circuit 10 to achieve its output.The drive circuit 12 is matched to the impedance of a piezo ceramicelement which causes the membrane to vibrate to ensure good energytransfer.

The microcontroller 11 generates a square waveform of 120 to 150 Hzwhich is sent to the drive circuit 12. The boost circuit 10 generates anominal 12V DC voltage required by the drive circuit 12 from an inputwithin the range of 4.75V to 5.25 V DC as per USB 2.0 electrical inputrequirements (released April 2000). The circuit is matched to theimpedance of the piezo ceramic element within the nebulizer head 3 toensure enhanced energy transfer. A drive frequency of 120 to 150 kHz isgenerated to drive the nebulizer head 3 membrane at close to itsresonant frequency so that enough amplitude is generated to break offdroplets and produce the aerosol. If this frequency is chopped at alower frequency such that aerosol is generated for a short time and thenstopped for a short time this gives good control of the nebulizer's flowrate. This lower frequency is called the “pulse rate”.

The drive frequency may be started and stopped as required using themicrocontroller 11. This allows for control of flow rate by driving thenebulizer head 3 for any required pulse rate. The microcontroller 11 maycontrol the ON and OFF times to an accuracy of milliseconds.

The nebulizer head 3 may be calibrated at a certain pulse rate bymeasuring how long it takes to deliver a known quantity of solution.There is a linear relationship between the pulse rate and the nebulizerflow rate. This may allow for accurate control over the delivery rate ofthe aqueous solution.

Because of use of the universal bus, in this case the USB cable 5 andthe USB plug 4, the controller 2 can achieve very wide-ranging controlof the nebulizer head 3. Also, it allows the controller 2 to beconnected to a host having data processing and USB communicationcapability (such as a host computer or a portable device) for upload ofinformation previously captured from the nebulizer head 3, or fordownload of configuration settings or other data to the controller 2. Incombination, the host and the nebulizer 1 form a system which mayadvantageously be used, for example, for clinical trials or controlledhospital or home treatment regimes.

The controller 2 can upload in various embodiments the followingnebulizer characteristics to the host:

-   -   power consumption, and/or    -   wet/dry state, and/or    -   nebulizer disconnect status, and/or    -   cable disconnect status, and/or    -   error or fault states, and/or    -   nebulization duration and time of nebulization.

The host can in various embodiments provide the following instructionsto the controller 2:

-   -   nebulization start/stop, and/or    -   nebulization time, and/or    -   nebulization flow rate, and/or    -   nebulization pulse rate, and/or    -   inspiratory/expiratory signal to enable phased nebulization.

This will allow the controller 2 to be controlled via a host, eitherlocally or remotely. The controller 2 may operate as a slave device,with the dosing regime determined by the host. This allows comprehensivecontrol and treatment monitoring for a wide variety of situations suchas in the home or in hospitals. If the controller is in communicationwith an external device, it can then act as a slave device and takecommands form the external device. If it is powered by an externaldevice, the mode of operation will be determined by the user input viathe ON/OFF (power) button 32 and in this case the controller can bethought of being in “master” mode.

In other embodiments, the controller may be in the form of a hand helddevice, and may in fact be a mobile phone programmed to generate a userinterface for nebulizer control. A specific mobile phone applicationcould be generated to enable control of nebulization.

The arrangement of having the USB plug 4, the USB cable 5, the smallhand-held controller 2, the proprietary cable 6 and the proprietary plug7 allows convenience and versatility in use. For example, as illustratedin FIG. 3 the cables 5 and 6 along with the controller 2 may be securedby ties to a ventilator tube. However, they may be attached to any othertubular or elongate member. This allows convenience of access bycare-givers and patients alike.

It will also be appreciated that the nebuliser can be plugged into anyhost system. The arrangement gives flexibility in a care-giving settingwhere there are multiple ventilators and patents. The USB interfaceallows link-up with a host device to allow remote control by acare-giver, for example, for control over the Internet to a host laptopcomputer into which the nebuliser is plugged.

Further, the extent of allowable local control may be limited to on/offcontrol by limiting scope of the interface on the controller 2, thedosing control (pulse rate, flow rate, frequency etc.) being controlledfrom a remote location via a the host system. The controller may executea program such as an “app” which allows a patient-specific dosing regimeto be downloaded from to a mobile/tablet/PDA. The local program willthen implement this new dosing regime.

There is excellent versatility because the nebuliser can be used with aventilator, car socket, laptop computer, desktop computer, or batterypack. Because the controller is essentially part of the cabling it maynot be by-passed accidentally.

The following are other benefits which arise from the invention invarious embodiments:

-   -   Increased portability due to elimination of need for additional        accessories, such as battery packs, AC/DC power adapters. These        are eliminated because of the common use of USB ports in general        electrical equipment, such as mobile phones, computers, and        medical electrical equipment    -   Eliminates need for supporting brackets.    -   Eliminates need for country-specific power adapters.    -   Can be used in remote areas where power is not available, for        example, using solar power, hand crank battery pack    -   Fewer components.    -   Low power consumption.    -   Plug and play operation    -   Can communicate with a host controller, with ability to collect        patient dosing data and communicate it to the host.    -   Avoidance of need to integrate a control PCB into medical        electrical equipment in order to operate from the ME GUI        (graphical user interface). For example, it is known at present        to integrate an Aerogen™ control PCB into a ventilator, to        enable operation of nebulizers via the ventilator interface. The        present invention will remove the need for such integration.    -   Compatibility/usability with wide variety of medical electrical        equipment (i.e. any equipment with USB port).    -   Can be powered by any of a range of devices such as USB battery        packs or portable solar panels.

The controller may be hand-held having a battery and power supply akinto that of a mobile phone.

The invention is not limited to the embodiments described but may bevaried in construction and detail.

1-12. (canceled)
 13. A nebulizer system, comprising: a nebulizer; a hostsystem; a first cable including power and data channels and having afirst plug connectable to the host system; a second cable includingpower and data channels and having a second plug connectable to thenebulizer; and a controller disposed between the first cable and thesecond cable, wherein the controller is configured to: receive power andone or more control signals from the host system via the first cable;generate one or more nebulizer drive signals based on the one or morecontrol signals; and deliver power and the one or more nebulizer drivesignals to the nebulizer via the second cable to generate aerosol viathe nebulizer according to the one or more nebulizer drive signals. 14.The nebulizer system of claim 13, wherein the host system includesmedical electrical equipment.
 15. The nebulizer system of claim 13,wherein the host system includes a ventilator.
 16. The nebulizer systemof claim 13, wherein the host system includes a computing device. 17.The nebulizer system of claim 13, wherein the first plug includes auniversal plug.
 18. The nebulizer system of claim 13, wherein thecontroller includes a housing remote from the nebulizer.
 19. Thenebulizer system of claim 13, wherein the one or more control signalsincludes one or more of a nebulization start/stop signal, a nebulizationtime signal, nebulization flow rate signal, a nebulization pulse ratesignal, or an inspiratory/expiratory signal to enable phasednebulization.
 20. The nebulizer system of claim 13, wherein thecontroller is further configured to: send information to the hostsystem, the information including one or more of a wet/dry state of thenebulizer, a nebulizer disconnect status, a cable disconnect status, anerror or fault status, or a nebulization duration and time ofnebulization.
 21. The nebulizer system of claim 13, wherein thecontroller includes a drive circuit, and the controller is furtherconfigured to: deliver the one or more nebulizer drive signals to thenebulizer via the drive circuit.
 22. A method for generating aerosol viaa nebulizer, comprising: delivering power and one or more controlsignals from a host system to a controller via a first cable having afirst plug extending from a first end of the controller, the first cableincluding power and data channels; generating one or more nebulizerdrive signals based on the one or more control signals via thecontroller; delivering the one or more nebulizer drive signals and powerto the nebulizer via a second cable having a second plug extending froma second end of the controller, the second cable including power anddata channels; and generating aerosol via the nebulizer according to theone or more nebulizer drive signals.
 23. The method of claim 22, whereinthe host system includes medical electrical equipment.
 24. The method ofclaim 22, wherein the host system includes a ventilator.
 25. The methodof claim 22, wherein the host system includes a computing device. 26.The method of claim 22, wherein the first plug includes a universalplug.
 27. The method of claim 22, wherein the controller includes ahousing remote from the nebulizer.
 28. The method of claim 22, whereinthe plurality of control signals includes one or more of a nebulizationstart/stop signal, a nebulization time signal, nebulization flow ratesignal, a nebulization pulse rate signal, or an inspiratory/expiratorysignal to enable phased nebulization.
 29. The method of claim 22,further including: sending information from the controller to the hostsystem, the information including one or more of a wet/dry state of thenebulizer, a nebulizer disconnect status, a cable disconnect status, anerror or fault status, or a nebulization duration and time ofnebulization.
 30. The method of claim 22, wherein the controllerincludes a drive circuit, and the method further includes: deliveringthe plurality of nebulizer drive signals to the nebulizer via the drivecircuit.
 31. A nebulizer system, comprising: a nebulizer; a host system;a first cable including power and data channels and having a first plugconnectable to the host system; a second cable including power and datachannels and having a second plug connectable to the nebulizer; and acontroller disposed between the first cable and the second cable, thecontroller including a housing remote from the nebulizer, wherein thecontroller is configured to: receive power and one or more controlsignals from the host system via the first cable, the one or morecontrol signals including one or more of a nebulization start/stopsignal, a nebulization time signal, nebulization flow rate signal, anebulization pulse rate signal, or an inspiratory/expiratory signal toenable phased nebulization; generate one or more nebulizer drive signalsbased on the one or more control signals; and deliver power and the oneor more nebulizer drive signals to the nebulizer via the second cable togenerate aerosol via the nebulizer according to the one or morenebulizer drive signals.
 32. The nebulizer system of claim 31, whereinthe host system includes a ventilator.